Tape drive paths not visible

[Guduru]

Hi ,

I have netbackup master running with 6.5.4 version which on Linux 6.2 Opetrating system. I'm trying to configure the NetApp VTL tape drives to this master.

I can see the robotic path but not tape drives for tpautoconf -t

did issue lip and re-scan and host rebooted too..but no luck :(

Can anyone have any idea what could be the issue?

Thank you,

Prasad

[Marianne]

Firstly, check your VTL config and ensure that tape drives have been assigned to the Linux server.

If SAN attached, verify zoning.

As long as OS does not see the devices, there is nothing that can be done from NBU point of view.

PS:

PLEASE upgrade NBU to 7.x - NBU 6.x reached EOSL over a year ago.

[mph999]

What do you see in 

cat /proc/scsi/scsi

[Guduru]

@Marianne - Everything is fine from VTL side.. and i can see the tape drives with out paths.

Checked Zoning too.. All ports are logged in

from the OS i can see the device files. in cat /proc/scsi/scsi

@Mph999 -- > I can see the tape drives from cat /proc/scsi/scsi but when i do tpautoconf -t or scan -tape ..i can't see the drive paths.

[Marianne]

Please show us 'cat /proc/scsi/scsi' output.

[mph999]

Odd, usually if you can see them in the OS scan should work.

Suspect you have some driver or firmware issue then, there is no config or adjustments that can be made for scan.  All it is doing is sending a scsi command to the device, which is either not receiving it, or if it is, is not responding.

Try this :

mt -f <device file to tape drive> status

then using the same path :

/usr/openv/volmgr/bin/scsi_command -d <device file to path>

[Guduru]

mph@ .. Here is the the responce i got for one of the tape drive

[root@xxxxxx ~]# mt -f /dev/sg4

bash: mt: command not found

[root@xxxxxx ~]#

[root@xxxxxx ~]# /usr/openv/volmgr/bin/scsi_command -d /dev/sg4

Inquiry data: removable dev type 1h HP      Ultrium 3-SCSI  022C

[root@xxxxxx ~]# 

[root@xxxxxxx ~]# cat /proc/scsi/scsi

Attached devices:

Host: scsi0 Channel: 00 Id: 00 Lun: 00

  Vendor: NETAPP   Model: VTL              Rev: 0001

  Type:   Medium Changer                   ANSI  SCSI revision: 02

Host: scsi0 Channel: 00 Id: 00 Lun: 01

  Vendor: HP       Model: Ultrium 3-SCSI   Rev: 022C

  Type:   Sequential-Access                ANSI  SCSI revision: 02

Host: scsi0 Channel: 00 Id: 00 Lun: 02

  Vendor: HP       Model: Ultrium 3-SCSI   Rev: 022C

  Type:   Sequential-Access                ANSI  SCSI revision: 02

Host: scsi0 Channel: 00 Id: 00 Lun: 03

  Vendor: HP       Model: Ultrium 3-SCSI   Rev: 022C

  Type:   Sequential-Access                ANSI  SCSI revision: 02

Host: scsi0 Channel: 00 Id: 00 Lun: 04

  Vendor: HP       Model: Ultrium 3-SCSI   Rev: 022C

  Type:   Sequential-Access                ANSI  SCSI revision: 02

Host: scsi0 Channel: 00 Id: 00 Lun: 05

  Vendor: HP       Model: Ultrium 3-SCSI   Rev: 022C

  Type:   Sequential-Access                ANSI  SCSI revision: 02

[root@xxxxxx ~]# 

[Marianne]

NBU needs the OS to see /dev/rmt device names.

You need to verify that sg as well as st device drivers are installed.

See Device Config Guide:  

Verifying the Linux drivers

To use SCSI tape drives and robotic libraries, the following drivers must be configured in the kernel or loaded as modules:

■ Linux SCSI generic (sg) driver. This driver allows pass-through commands to SCSI tape drives and control of robotic devices.

■ SCSI tape (st) driver. This driver allows the use of SCSI tape drives.

■ Standard SCSI driver.

■ SCSI-adaptor driver.

Verify that the drivers are installed and loaded in the kernel. You can use the

/sbin/lsmod command to verify that the st and the sg drivers are loaded in the

kernel. Example output is as follows:

Module Size Used by

sg 14844 0

st 24556 0

The standard Enterprise Linux releases have the sg and the st modules available for loading. The modules are loaded as needed. Also, you can load these modules if they are not in the kernel. Use the following commands:

/sbin/modprobe st

/sbin/modprobe sg

[mph999]

Marianne beat me to it ....

[Guduru]

Drivers are there..

[root@xxxx ~]# lsmod | egrep -i "sg|st"

sg                     30124  0 

osst                   54494  0 

st                     38660  0 

[root@xxxx ~]# 

[mph999]

Under /dev do you have 'nstxx' files for the drives

EG. /dev/nst0

/dev/nst1  

.. and so on

[Guduru]

yes, we have those device files(nst)

[Marianne · Accepted solution]

Please show us output of :

ls -l /dev/nst*

Have you checked all compatibility guides?
Hardware and OS?

According to NBU 6.x compatibility guide, RHEL 6.x was only supported as from NBU 6.5.6.

And all NBU 6.x versions reached EOSL more than a year ago....

Master Compatibility List: http://www.symantec.com/docs/TECH59978

[Guduru]

Hmm..I missed out to check it. will do that

we aware that  NBU 6.x versions reached EOSL but this machine is only for restores..its not doing any backup.

Here infrmation requested

this is UCS box with Red Hat Enterprise Linux Server release 6.2 which is installed NetBackup-RedHat2.6 6.5.4 on it.

[root@xxxxx ~]# ls -l /dev/nst*

crw-rw---- 1 root tape  9, 128 Oct 18 01:34 /dev/nst0

crw-rw---- 1 root tape  9, 224 Oct 18 01:34 /dev/nst0a

crw-rw---- 1 root tape  9, 160 Oct 18 01:34 /dev/nst0l

crw-rw---- 1 root tape  9, 192 Oct 18 01:34 /dev/nst0m

crw-rw---- 1 root tape  9, 129 Oct 18 01:34 /dev/nst1

crw-rw---- 1 root tape  9, 225 Oct 18 01:34 /dev/nst1a

crw-rw---- 1 root tape  9, 161 Oct 18 01:34 /dev/nst1l

crw-rw---- 1 root tape  9, 193 Oct 18 01:34 /dev/nst1m

crw-rw---- 1 root tape  9, 130 Oct 18 01:34 /dev/nst2

crw-rw---- 1 root tape  9, 226 Oct 18 01:34 /dev/nst2a

crw-rw---- 1 root tape  9, 162 Oct 18 01:34 /dev/nst2l

crw-rw---- 1 root tape  9, 194 Oct 18 01:34 /dev/nst2m

crw-rw---- 1 root tape  9, 131 Oct 18 01:34 /dev/nst3

crw-rw---- 1 root tape  9, 227 Oct 18 01:34 /dev/nst3a

crw-rw---- 1 root tape  9, 163 Oct 18 01:34 /dev/nst3l

crw-rw---- 1 root tape  9, 195 Oct 18 01:34 /dev/nst3m

crw-rw---- 1 root tape  9, 132 Oct 18 01:34 /dev/nst4

crw-rw---- 1 root tape  9, 228 Oct 18 01:34 /dev/nst4a

crw-rw---- 1 root tape  9, 164 Oct 18 01:34 /dev/nst4l

crw-rw---- 1 root tape  9, 196 Oct 18 01:34 /dev/nst4m

crw-rw-rw- 1 root root 99,  32 Nov  8 01:21 /dev/nst99

[root@xxxx ~]#

[Marianne]

I am missing something....

Why config a new VTL on a server that needs to perform restores only?

Please repeat scsi_command with /dev/nst0 device name:

 /usr/openv/volmgr/bin/scsi_command -d /dev/nst0

Can you mount a tape with VTL tools and use tar to read/write to /dev/nst0?

[Guduru]

Why config a new VTL on a server that needs to perform restores only?

its not new VTL. this VTL was already used for backups happend on this machine before hardware migration. but i have few VTL tapes which i want to duplicate (which are failing exports) to physical tapes.

for same trying to configure the tape drives again (as HBA wwpns changed)

[root@ux3slv13 ~]#  /usr/openv/volmgr/bin/scsi_command -d /dev/nst0

Error opening /dev/nst0, could not determine passthru device path for /dev/nst0

[root@ux3slv13 ~]# 

Can you mount a tape with VTL tools and use tar to read/write to /dev/nst0?

didn't configure the robot . will give the result in few min

[Marianne]

root@ux3slv13 ~]#  /usr/openv/volmgr/bin/scsi_command -d /dev/nst0

Error opening /dev/nst0, could not determine passthru device path for /dev/nst0

So... now we know why tpautoconf is not working.

Maybe best to start all over and first check all compatibilities.